Electric furnace



Sept. 15, 1925. 1,553,618

L. D. KAY

ELECTRIC FURNAC E Filed May 22, 1923 4 Sheets-Sheet 1 Sept. 15, 1925.

L. D. KAY

ELECTRI C FURNACE Filed May 22, 1923 4 Sheets-Sheet 2 Sept. 15, 1925.1,553,618

- L. D. KAY

ELECTR I C FURNACE Filed May 22, 1923 4 Sheets-Sheet 3 Sept. 15, l 925.

L. D. KAY

ELECTRIC FURNACE Fild May 22,

1923 4 Sheets-Sheet 4 Patented Sept. 15, 1925.

UNITED STATES LLOYD D. KAY, OF LOS ANGELES, CALIFORNIA.

ELECTRIC FURNACE.

Application filed May 22, 1923. Serial No. 640,71-1.

To all "whom it may concern:

Be it known that I, LLOYD D. KAY, a citizen of the United States,residing at Los Angeles, county of Los Angeles, and State of California,have invented a new and useful Electric Furnace, of which the followingis a specification.

This invention relates to furnaces, and, while many features of theinvention may be utilized under other circumstances, the invention isexpected to be especially useful as applied to an electric furnace. In acertain type of electric furnace, the body of the furnace is mounted onan axis so that it is capable of being tilted when the molten metal isbeing poured. In orderto tilt the furnace, gears have been employed, forexample, a worm-wheel and worm, but where a worm-wheel or gear-wheel isemployed there is always a slight'amount of back-lash present which willpermit a slightlost motion in operating the device; The presence ofthis'lost motion is objectionable for many reasons, among which is thefact that'the' ticularly.illustrating the device for adjustmg the tiltofthe furnace.

shifting of the molten bath from one side of the furnace to the otherside may suddenly take up the back-lash and give the molten metal animpetus toward the low end of the furnace; this is dangerous.

furnace, it is desirable to have the metal run off ata level as farremoved as possible.

' 'wtr'i'c cables'ito them from the slag.

Theg'eneral object of this invention is to provide a-furnace of simpleconstruction having means for overcoming these difficulties and in whichthe metal in the furnace is counter-balanced: also to provide a'construction which will enable the furnace to' be tilted without theexertion of great force; also to provide a furnace that is soconstructed that the metal poured from it will be drawn off as far aspossible from the floating slag.

v A further object is to provide simple means for supporting andadjusting the electrodes and to provide simple means forcounterbalancing them and compensating in In'pouring the metal from sucha tilting The invention consists in the novel parts and combination ofparts to be described hereinafter, all of which contribute to produce anefficient electric furnace.

A preferred embodiment of the invention is described in the followingspecification, while the broad scope of the invention is pointed out inthe appended claims.

. In the drawings:

Figure 1 is a front elevation of a furnace embodying my invention.

Figure 2 is a plan of the body of the furnace with the cover removed andshowing other parts broken away. ..-Figure 3 is a cross-section throughthe furnace body taken on a line 33 of F igure 2.

1 Figure 4 is a side elevation particularly illustrating thecounterweight mechanism.

.3 Figure 5 is a plan illustrating the details of the means.for,.adjusting.the electrodes and their counterweights. I

Figure 6 is a side elevation showing'a portion of 'theibodyof thefurnace and par- Figure 7 isua seotiontakenabout on the .line77 ofFigure 6 and,particularly illustrating the details of the adjustingvscrew.=

Figure 8 is a 5 plan particularly illustrating .the details, of theelectrode frames and" shQwingthe-means for connecting the elec- Figure'9is a verticalsectionftaken about {on the line 99 of Figure jSillustrating the porting the'electrodes in the holders. I .Flgure' 10 isa vertical section taken about on the line 1010 of F ignre 8 u on anenlarged scale and further illustratlng details of the connection fortheelectric cable's.

Figure 11 is a vertical section taken about on the line 1111 of;Figure'S and showing the connection for the fixed end of the cable. Inpracticing the invention, I provide a furnace body which is supported soas to rotate on a substantially horizontal axis. This body is providedwith one ormorepouring spouts. I provide an adjustable means forpositively holding this body against rotation on the axis in eitherdirection. By the term positively holding I mean to say that the deviceI employ is constructed so it is devoid of back-lash, hence it isimpossible for a slight-rockingamovement of the body to take place onits axis unless that movement is caused by the adjustment of theadjusting means. The body 1 may be formed of a 5 sheet metal shell with'firebri'ck lining 2 and provided with a pouring spout 3 at each end.This body is preferably of slightly elongated form and supported to rockin its middle plane on a substantially horizontal axis near its centerof gravity, for-which purpose the opposite sides of the shell areprovided with trunn'ions 4. These trunnions may be supported in pedestalbearingsb which support the'body over an ash pit 6. The furnace maybe'provide'd with a cover '7 of any suitable construction through whichaplurality of electrodes '8 pass, each electrode being passed through aninsulating sleeve 9 which supports it effectively uponthe cover.

I provide simple means for raising and lowerin the electrode and forcounterbalanci'ng t em in such away that when the electrode becomes wornand is fed down- "g'wardly so thatits center of gravity approaches'theaxis of rotation of the furnace, then there is a correspondingmovement of its 'cou'i'ite'rweight toward the axis ofrotation.' In'tliis"way, "I-not'only counter-bal- "since each electrode," but-Icompensate for the i'nward feeding I movement 'of the electrode, therebypreventing :the weighv-of the electrodes "frominterferingin-any way withthe "tilting ofth'e furnace? Furthermore, I 'mi'nint these electrodes ona frame which is ways- This frame has aiimpw'ai'dextensmn 12about inline with the-'si'tte offthe wall bf Z the fiirriacejfanditalsolhasjadownward ex-'- tension "13 'vvhilr' 'is' located Qnfthe outer side I erdnaadjacait pefl'estal' beai-ing The extehsi'ori' 12 operates as a"guide for the electrodes for which --purpose "it is preferably Icon'sfr'u cted bf "a plurality "of I -beams or trod'e"fran'ic 15 (seeFigs-*1 and 8): These -"clec'trddframes maybe formed with an 'upper arm16 andiai lower-arm 17,ea0h arm being" provided: with a yoke 1 8(see-Fig. '8)

at' its'"innerendbarryingrollers 19 which "engage 'infthe channels onopposite sides of the I-beam 'At thempperfend of each I-beam guidesheaves o'r pulleys *20 are provided over which a cord- 21 passes'whichis attached at 22 to itscorresponding electrode frame. I i The lowerend-*of this cord 21 is attached toa device of special constructionwhich may be operated at will to lower the electrode, and this operationof lowering the rigid with the body of' the -flirnace and,

corresponding counter-weight 23. In orderto adapt these counter-weightsto use with electrodes of difi'erent weights, each counterweightconsists of an open receptacle (see Fig. 4) the interior of which may.be filled with scrap-iron 28 or similar material,-

The cords 21 and 27 wrap about thedru m in opposite directions so thatwhen the upper cord 21 is payed out to permit theelectrode 8 to descend,then'the corresponding counterweight will be'slightly raised in itsguideway. Any suitable means may be provided for operating the drums'26. In 5 .I. illustrate a simple worm wheel 29 rigid with the: drum andactuated by a worm 3Q iwith an operating 'wheel 31 (see {Fig In orderftO- provide a considerable, depth of-metal alt-the pouring spout, Iprefer to construct the ends of the'bas1ii 32 in the firebrick liningsothat the channel (through whi'chthe metal flows invgoing to the spout-fl ends of thebasin;withi convergmgisides or side-walls 33. In -this-way, ;as. theu metal flows outqinto-the end of the .iof-"the an'etalincreasesand, hence the rnetal fwhich flows out of thespout; wilLbetaken from a considerable depth belowQtdre k s lag floating on "the;surfacei of the I molten rmass.

1 is very much contracted-in widthfa n d 7700 is mpl he is p ypaaprgridheih The bottom (if the furnacehas upwardlyjn 1 clined end wallsindicated by the dotted lines- 34 in- Fig. 4. The slagis held' by, agate 3; i a;

By reason o'f-the constant raisingand lowering of theelectrodesyany;ca.ble connection is subjected to-slight movement. Ipro "vide a.connection of; simple construction which-"can be readily made and whichmsures an ample area of contact at the connection as well as insuring asecure connec-;;

tion. In order to accomplish this,, I ,provide an electrode holder 35forieach elec trode with atapered socket :36 which is in metallicconnection t he hglderi For convenience, this, tapered socket {may be;

formed in a-small bracket 37 bo lte dion the side of the electrodeholder. The bracket 37 is preferably constructed of copper or brass andthe tapered s0cket36 isisi'm'ply a tapered bore. This bore receivesja"tapered,

plug 38 which has the same angle of taper as the socket, and this plugis secured to the end of the flexible cable 39 which carries thecurrentto or from the electrode. Plug 38 is simply in the form of a hollow conewith opening 40 at its large end. In securing the plug to the end of thecable, the end of the cable is bared'of insulation and the plug is heldin a vertical position and filled with molten metal such as lead. The 0bareend of the cable is then thrust through the opening 40 and jammeddown to the bottom or small end of the plug. This will displace aconsiderable amount of lead, but leaves the inner chamber of the plugcompletely filled with lead, which operates as a good conductorconnecting all sides of the end of the cable with the adjacent wall ofthe plug. The plug may be held in the socket by means of a threaded stem11 at its small end which passes loosely through an opening 42 at theinner end of the socket and is secured in place bya nut 43. The fixedend of the cable 39 is preferably provided with a similar plugandsocketconnection (see Fig. 11)" which the socket 4-1 is constructed aspart of a fixed bracket45 which is mounted'on' an insulating support46.This socket receives a taperedplug 47 secured to the cable in the sameway as described in con .nection with 'the plug 38'. In order to alm :Alow for .the'tilting of the furnace and the j ra'isingorflowering"0f"the "electrodes the "cable 39p'referably is permittedtohang in loop; (see Fig. 1). .In order totilt the furnaceilatjavill,Ifprovide an adjusting der vic'e whi ch isl preferably .inthe form 'of a 'crew d'evi'ce 48 "(see Fig. 6). This gialyfc actpd -wathe body of the fur- ":nace -Foi" this purpips'e, thejarm {19 may red 21ectlyfto' the' outermost truncatedito'receive a l oose'pin 50"arid inthis piii a feed-screw 51 'ha's'a swivel head 52.

The outer} end of the: adjusting screw 51 carries'a I' ut 5:3, .thesides o f'which are formed into pinsonpintles 54' which rock in theupper e'nd of the pedestal bracket 55. This nut 53is'threaded"preferably with a square'thread tofit the square thread onthe screw 51, and the endof the screw is pro vided with,a-liand wheel 56for rotating it.

' 'lVi'th this organization of parts, it will be noted that the device48 will hold the body 55 positively against a slight movement in eitherdirection on its axis. At the same time, the hand-wheel 56 and thethreads on the screw 51 give sufficientleverage to enable the molder totilt the furnace at will.

In order to hold the electrodes 8 in position, each holder 35 is formedwith a tapered bore 57, the large end of which is disposed upwardly (seeFig. 9), and in this bore I place a pair of tapered bushings 58 whichhave flanges at their upper ends, and are inend of this arm isbifurserted from above. These bushings are bored to the diameter oftheelectrode so that when they are pressed downwardly they act as wedges inthe conical bore 57 and clamp the electrode in place. There is nothingconnected to them; they are freely movable upwards with their pathunobstructed so that they can be instantly dislodged by a blow under theflange.

Each electrode holder 35 is effectively insulated from the electrodeframe which supports it by means of an insulating plate 59 to which theholder is securedby means of insulated bolts 0 (see Figs. 8 and 9).

The counterweights 23 are placed at such a level that when cooperatingwith the electrodes, the weights may project below the lower edge of theguide plate 24. \Vhen the furnace is to be tilted, the electrodes shouldbe lowered, and the counterweights raised to any point desired to enablethe weights to operate as an effective counterbalance for themetal asthe furnace tilts. As the furnacetilts, of course the weights restagainst the sides of the-frame bars, 25, and so they swing away from thevertical plane of the furnace. In this way their lever arm 'as acounterbalance increases, thefurther the furnace is tilted. i

' In order to guide the back-plate 24 as the furnace is tilted, Iprovide. two .rollers- 61, which are carried respectively in brackets62. One of theserbracketsis attached to the pedestal 5 at one side and'the other'at the other side (see FigsL'l and=14)..-

It is understood that the embodiment of I the invention described.hereiniisz onl'y -one ociate dwith mn arm 49 which is of manyembodiments this invention may take and'I do not wish to be limitedinthe practice of my invention nor=in my-claims to the particularembodiment set forth. 13%;

What claim is: ,1 1. In an electric furnace, the combination of a bodyhaving a.'fire-brick lining,

trunnions supporting the body tocrotate on a substantially horizontalaxis,- .a pouring spout carriedby' the body at fits end, a pin looselymounted in the arm, an adjusting screw having a swivel connectionwiththe pin, a nut mounted'to rock on a=.fix'd.axis,-

and having a thread connection with the screw, 'and a hand wheelattached directly to the screw for rotating the screw to rock the armand tilt the furnace body on its axis.

2. In an electric furnace, the combination of a fire-brick lined body,means for supporting the same to rotate on a substantially horizontalaxis, an electrode guiding frame carried by the body and extendingupwardly above the same, an electrode guided on the guide frame andextending down into the furnace, a counterweight for the electrodesupported so as to move about the said horizontal axis when the body istilted, and carried below the said axis of &

rotation, means for raising and lowering the electrode, and means fortilting the body on .its axis of rotation.

3. In an electric furnace, the combination of a fire-brick lined body,means for supporting-the same to .rotate on a substantially horizontalaxis, an electrode guiding frame carried :by the body and extendingupwardly above then-same, an. electrodeguided on the guide frame-andextending down into the furnace, a counterweight for the electrodecarried-in the guiding frame below the said axis of rotation, meansconnected with the electrode and the counterweight operating :to lowerthe electrode and raise the counter --weight, and means for tilting thebody on its axzis of rotation.

4. :In-an electric furnace, the combination of=a dire-brick lined body,means for supporting the same to rotate on a substanatiaillyrhorizontalaxis, a guide frame carried "by the body and having an upwardextensionafor-guiding an electrode and a downfwardaextension forguidinga counterweight, an electrode frame guided on the guidefn'ame andhaving means for holding an electrode, a counterweight guided in the:lower portion of the guide frame below the axis of rotation of thebody, means for raising :and lowering the electrode frame andthecou'nterweight, and means for tilting the body on its axis ofrotation.

5. 'In an electric furnace, the combination of "a fire-brick lined body,means for supporting'thesame to rotate on a substantiallv horizontalaxis, a :guide-frame carried by "the body and having an upward extensionfor guiding-an electrode and a downward extension for guiding .acounterweight, an electrode frame guided on the guide-frame and havingmeans for holding an electrode, a counterweight guided'in the-lowerportion o'f the guide-frame below the axis of rotal tlOlbOf the body,means for raising and lowering the electrode frame and thecounterweight, means for tilting the body on its :axis of'rotation, anda flexible electric cable heldifixed :at-one end and connected at its.=other end :with the electrode.

6. Inaan electric furnace, the combination of a ifire-br'ick lined body,means for supporting the same=to rotate on a substantially horizontalaxis, a guide-frame rigid with sion, means for raising and lowering each(electrode and its .conrespondmg counterweight, and means for tiltingthe body on its axis of rotation.

7. In an electric furnace, the combination of a body, means forsupporting the same to V rotate on a substantially horizontal axis, anda .spout carried by :the body at its ends, a fire brick lining forminga-basin within the body and having sides converging toward the saidspout, whereby when the furnace is tilted'the depth ,O-f metal .isincreased in the vicinity of the pouring spout, thereby facilitating the,pouring of the metal from a depth 'below the slag.

:8. In an electric furnace, the combination of an electrode holderhaving .a tapered socket metallically connected therewith an insulatedcable,a tapered plug receiving the end of the said cable, a packing ofconductive material surrounding the end of the cable within the ,plug,and providing metal between the side of the cable and the wall .of theplug, and means for securingthe plug in the tapered socket.

9. In an electric furnace, the combination of a body having a fire-brick'-lining,,means for supporting .etheobody .to rock on a fixedsubstantially horizontal axis passing trans versely through .the body, apouring spout carried by the body at its end, an arm rigid,

with the body, a .nut-and-screw device associated with the arm forswinging the arm in either direction to tilt the furnace body on itsaxis and having a swivel support for the screw at the arm and anotherswivel support for the'screw ata fixed point, and

a hand wheel connected directly to the nutand-screw device for rotatingthe screw in unison with the hand wheel.

Si ned at Los Angeles, California, this 8th day of May, 1923.

LLOYD D. KAY.

